1. Field of the Invention
The present invention generally relates to a cold plate with vortex generator, especially to the cold plate with vortex generator having symmetrical ribs for producing a pair of positive or negative vortexes.
2. Description of the Prior Art
Please refer to FIG. 1, which shows a layout of a cooling device in prior arts. The arrangement of a cooling fan 2 cooperating with a heat sink 3 assembled on an electrical component 1 to cool down the electrical component 1 is the most common usage and has been adopted for a couple of years; however, due to quick development, electrical component is getting smaller and its process performance is getting better, while heat load on each component is much more than before. As the aforesaid arrangement in prior art, the heat load is about 60 W and not qualified to meet the present requirement, which therefore extremely damages both the electrical component and the system using that component.
To overcome the problem of heat load in prior art, another cooling method using enforcing mechanism with liquid is developed, such as the method disclosed in Taiwan Patent Numbers 537442, 437992, 509349 and 450378. These patents disclose the method using coolant for heat load. Referring to FIG. 2 and FIG. 3, which show a cold plate and a heat transfer system employing the cold plate in prior arts. Traditionally, a cold plate 4 has a recycling tube 41 for coolant, two ends of the recycling tube 41 individually connect to an input tube 42 and an output tube 43. The cold plate 4 is adhered on the electrical component 1. Continuously the input tube 42 is connected to a pump 5, and the pump 5 is connected to a tank 6, and the output tube 43 goes through a radiator 7, a fan 8 and goes back to the tank 6 to form a complete cooling cycle. Following is how coolant works for heat load: the pump 5 pumps up the coolant first from the tank 6, then the coolant traverses the input tube 42 and the recycling tube 41 of the cold plate 4. Due to the cold plate 4 adhered on the electrical component 1, the coolant can dissipate the heat generated by the electrical components 1 out of the output tube 43, afterward, the coolant with heat is cooled down by the radiator 7 and the fan 8 and flows back to the tank 6, thereby the heat is exhausted to the air. Again the pump 5 draws the coolant out from the tank 6 and so on to start another cooling cycle.
Referring to FIG. 4, which is a diagram showing the formation of a thermal boundary layer in prior arts. As seen, the coolant 9 generates convection effect on the surface of the electrical component 1, Since the thermal boundary layer 91 is with high temperature, it is as a barrier for convection of the coolant plate and the coolant 9A, therefore the heat transfer effect is down.
For the issue of insufficient heat transfer derived from the thermal boundary layer effect, in order to have an average and mixed convection for the fluid on two sides of the thermal boundary layer, the common skill used at present is the method of producing vortexes. Such skill can be found in Taiwan Patent Numbers 535854, 511705, 446109 and 257347. All of these prior arts adopt vortexes to disturb the thermal boundary layer for promoting heat transfer effect; and, the prior arts also improve the structures of radiating blades or radiating fins, such as in Patent Numbers of 446109 and 511705. Mainly, the vortex generator is designed to surround the coolant tube, hence vortexes are produced between the coolant tube and the vortex generator while fluid getting past the coolant tube; the mixture for fluid is more complete to approach better heat conduction.
According to aforesaid, producing vortexes to mix fluid has been taken on for a couple of years, but the improvement has never been focused on “liquid-cooling cold plate”. In the near future, the requirement of the heat load of electronic component will be about 200 W, more, the heat flux required is approximately 125 W/cm2, therefore the tendency of high processing speed, small sizes and light weight in electrical field makes the heat load become a very important issue.